11-Step Enantioselective Synthesis of (−)-Lomaiviticin Aglycon

Enantioselective Synthesis of the Elaiophylin Aglycon.

Elaiophylin (1) was isolated in 1959 by Arcamone and co-workers from cultures of Streptomyces melanosporus.1 Subsequently, this natural product has also been obtained from other strains of Streptomyces.2 Structure elucidation of 1, including assignment of absolute stereochemistry, was based on chemical degradation,3 NMR studies,4 and ultimately X-ray crystallographic analysis.5 Isolation and ch...

Enantioselective synthesis of the lomaiviticin aglycon full carbon skeleton reveals remarkable remote substituent effects during the dimerization event.

Total Synthesis of Putative 11-epi-Lyngbouilloside Aglycon

We report here the total synthesis of 11-epi-lyngbouilloside aglycon. Our strategy features a Boeckman-type esterification followed by a RCM to form the 14-membered ring macrolactone and a late-stage side chain introduction via a Wittig olefination. Overall, the final product was obtained in 20 steps and 2% overall yield starting from commercially available 3-methyl-but-3-enol. Most importantly...

Nine-step enantioselective total synthesis of (+)-minfiensine.

An enantioselective total synthesis of the Strychnos alkaloid (+)-minfiensine has been accomplished. Prominent features of this synthesis include (i) a new enantioselective organocatalytic Diels-Alder/amine cyclization sequence to build the central tetracyclic pyrroloindoline framework in four steps from commercial materials and (ii) a 6-exo-dig radical cyclization to forge the final piperidiny...

Nine-step enantioselective total synthesis of (-)-vincorine.

A concise and highly enantioselective total synthesis of the akuammiline alkaloid (-)-vincorine has been accomplished. A key element of the synthesis is a stereoselective organocatalytic Diels-Alder, iminium cyclization cascade sequence, which serves to construct the tetracyclic alkaloid core architecture in one step from simple achiral precursors. The challenging seven-membered azepanyl ring s...